| if I were driving it on a daily basis. The first 120 miles were from Daytona to Gainesville where I kept the RPMs in various conditions as well as varying the load and boost. I kept a hawk's eye on oil pressure, coolant temperature, and wideband O2 information. I also ran the engine around 210F for the entire 120 mile trip. The following day I inspected the powerplant to ensure there were no leaks of coolant or oil, no loose or blown vacuum lines/hoseclamps, etc. Then I drove it 8 miles to the Gainesville International Raceway and participated in a roadcourse track event. The car was run for 4 15-minute sessions on pumpfuel and at around 18psi of boost as I would normally have driven it: this includes a lot of high-load, sweeping RPMs from 2K to 8K, unloaded high-revs (during de-cel); all possible engine conditions. The car ran without flaw. It was later dyno tuned over several sessions while eliminating a lack of fuel problem (due to the sub-par pumps used) and the car put down 666RWHP at 600RWTQ. The clutch began slipping at 600RWTQ, which is MUCH higher than I anticipated it would hold. There was obviously no detriment to the clutch in the break-in process I used for the engine. The key with the new clutch is not to load a new clutch such that it slips. If it slips before it is seated, it will not seat properly. I drove some 3100 miles to and from Dallas (ZCON '06), participated in the roadcourse at MSR and the auto-x at the speedway. No issues with the car burning oil, no smoking turbos, although the electric water pump did have a small, slow leak at the shaft seal (which basically required about a pint of coolant added for every gastank refill). The car was later taken back to Gainesville and ran an 11.95ET at 124MPH on pumpfuel and street tires at 18psi. The car now has 8400 miles on it, running strong, no leaks, turbos are happy. Performed a compression test a few weeks ago and all cylinders are spot-on. I will be dropping the crossmember and oil pan to inspect the rod bearings at the end of the year as preventive maintenance and replacing them if needed. I've done the break-in process both ways at this point: easy for ~1000 miles and then drive it as normal as well as running the car as I normally would from 0 miles. There isn't any difference I have noted in what effect it has on the engine. All of the engines I have built were strong for their modification level and never suffered failures as a result of a particular break-in procedure. I haven't seen any evidence that clearly shows that there is a difference. It was nice not having to waste 1000 miles until I got to enjoy it, but that wasn't the reasoning behind the process I used. "Motoman" details a lot of investigation he went through on 4-stroke motorcycle engines to determine if there is a difference in break-in processes and his findings were a motivational factor in my decision. Getting the rings seated really is the only component that "breaks-in" per-se; everything else just starts wearing out as the tolerances of all other contact surfaces are of significantly greater precision and hydrodynamic in nature. My engine unfortunately isn't the best testbed for drawing a conclusion on the longevity effects of this process, at least, in terms of the bottom-end's bearings and journals. My crankshaft underwent a significant amount of milling when I reduced its weight by 8lbs and the effects of this process on longevity aren't fully known. My suggestion: do some research and make a decision that makes you feel good - that's about as good as it will get.
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[ agpowers@bellsouth.net ] Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the tailor.
Albert Einstein
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